/*
* core_channel_read
* -----------------
*
* From from the local buffer and write back to the requester
*
* Takes TLVs:
*
* req: TLV_TYPE_CHANNEL_ID -- The channel identifier to read from
* req: TLV_TYPE_LENGTH -- The number of bytes to read
*/
DWORD remote_request_core_channel_read(Remote *remote, Packet *packet)
{
DWORD res = ERROR_SUCCESS, bytesToRead, bytesRead, channelId;
Packet *response = packet_create_response(packet);
PUCHAR temporaryBuffer = NULL;
Channel *channel = NULL;
do
{
if (!response)
{
res = ERROR_NOT_ENOUGH_MEMORY;
break;
}
// Get the number of bytes to read
bytesToRead = packet_get_tlv_value_uint(packet, TLV_TYPE_LENGTH);
channelId = packet_get_tlv_value_uint(packet, TLV_TYPE_CHANNEL_ID);
// Try to locate the specified channel
if (!(channel = channel_find_by_id(channelId)))
{
res = ERROR_NOT_FOUND;
break;
}
lock_acquire( channel->lock );
// Allocate temporary storage
if (!(temporaryBuffer = (PUCHAR)malloc(bytesToRead)))
{
res = ERROR_NOT_ENOUGH_MEMORY;
break;
}
switch (channel_get_class(channel))
{
// If it's buffered, read from the local buffer and either transmit
// the buffer in the response or write it back asynchronously
// depending on the mode of the channel.
case CHANNEL_CLASS_BUFFERED:
// Read in from local
res = channel_read_from_buffered(channel, temporaryBuffer,
bytesToRead, (PULONG)&bytesRead);
break;
// Handle read I/O for the pool class
case CHANNEL_CLASS_POOL:
// If the channel has a read handler
if (channel->ops.pool.read)
res = channel->ops.pool.read(channel, packet,
channel->ops.pool.native.context, temporaryBuffer,
bytesToRead, &bytesRead);
else
res = ERROR_NOT_SUPPORTED;
break;
default:
res = ERROR_NOT_SUPPORTED;
}
// If we've so far been successful and we have a temporary buffer...
if ((res == ERROR_SUCCESS) &&(temporaryBuffer) && (bytesRead))
{
// If the channel should operate synchronously, add the data to theresponse
if (channel_is_flag(channel, CHANNEL_FLAG_SYNCHRONOUS))
{
// if the channel data is ment to be compressed, compress it!
if( channel_is_flag( channel, CHANNEL_FLAG_COMPRESS ) )
packet_add_tlv_raw(response, TLV_TYPE_CHANNEL_DATA|TLV_META_TYPE_COMPRESSED, temporaryBuffer, bytesRead);
else
packet_add_tlv_raw(response, TLV_TYPE_CHANNEL_DATA, temporaryBuffer, bytesRead);
res = ERROR_SUCCESS;
}
// Otherwise, asynchronously write the buffer to the remote endpoint
else
{
if ((res = channel_write(channel, remote, NULL, 0, temporaryBuffer, bytesRead, NULL)) != ERROR_SUCCESS)
break;
}
}
} while (0);
if( channel )
lock_release( channel->lock );
if (temporaryBuffer)
free(temporaryBuffer);
// Transmit the acknowledgement
if (response)
{
packet_add_tlv_uint(response, TLV_TYPE_RESULT, res);
packet_add_tlv_uint(response, TLV_TYPE_LENGTH, bytesRead);
packet_add_tlv_uint(response, TLV_TYPE_CHANNEL_ID, channelId);
res = packet_transmit(remote, response, NULL);
}
return res;
}
/*
* Channel completion routine dispatcher
*/
DWORD _channel_packet_completion_routine(Remote *remote, Packet *packet,
LPVOID context, LPCSTR method, DWORD result)
{
ChannelCompletionRoutine *comp = (ChannelCompletionRoutine *)context;
DWORD channelId = packet_get_tlv_value_uint(packet, TLV_TYPE_CHANNEL_ID);
Channel *channel = channel_find_by_id(channelId);
DWORD res = ERROR_NOT_FOUND;
dprintf( "[CHANNEL] _channel_packet_completion_routine. channel=0x%08X method=%s", channel, method );
// If the channel was not found and it isn't an open request, return failure
if (!channel && strcmp(method, "core_channel_open"))
return ERROR_NOT_FOUND;
if ((!strcmp(method, "core_channel_open")) &&
(comp->routine.open))
res = comp->routine.open(remote, channel, comp->context, result);
else if ((!strcmp(method, "core_channel_read")) &&
(comp->routine.read))
{
ULONG length = 0, realLength = 0;
PUCHAR buffer = NULL;
// Get the number of bytes written
length = packet_get_tlv_value_uint(packet, TLV_TYPE_LENGTH);
// Allocate storage for it
if ((length) && (buffer = (PUCHAR)malloc(length)))
{
memset(buffer, 0, length);
channel_read_from_buffered(channel, buffer, length, &realLength);
}
res = comp->routine.read(remote, channel, comp->context, result,
buffer, realLength);
if (buffer)
free(buffer);
}
else if ((!strcmp(method, "core_channel_write")) &&
(comp->routine.write))
{
Tlv lengthTlv;
ULONG length = 0;
// Get the number of bytes written to the channel
if ((packet_get_tlv(packet, TLV_TYPE_LENGTH, &lengthTlv)
== ERROR_SUCCESS) &&
(lengthTlv.header.length >= sizeof(DWORD)))
length = ntohl(*(LPDWORD)lengthTlv.buffer);
res = comp->routine.write(remote, channel, comp->context, result,
length);
}
else if ((!strcmp(method, "core_channel_close")) &&
(comp->routine.close))
res = comp->routine.close(remote, channel, comp->context, result);
else if ((!strcmp(method, "core_channel_interact")) &&
(comp->routine.interact))
res = comp->routine.interact(remote, channel, comp->context, result);
// Deallocate the completion context
free(comp);
return res;
}